Impact in participatory health research

The idea for this special issue arose from the first International Scientific Meeting on the Impact of Participatory Health Research organized by the International Collaboration for Participatory Health Research (ICPHR), the German Network for Participatory Health Research (PartNet), the Institute of Population and PublicHealth,Canadian Institutes ofHealth Research (CIHR), and Community-Based Research Canada (CBRC). The conference took place in June 2015 at the Center for Interdisciplinary Research (ZiF) in Bielefeld, Germany. Experts in PHR from eleven countries met to launch an international discussion on what impact means in the participatory research process, how to maximize the impact of the research, and how to observe and document what impact has occurred. Several of the themes discussed at the conference are addressed in this issue.